Transport lock assembly, and a medicament delivery device comprising the transport lock assembly

ABSTRACT

A transport lock assembly for a medicament delivery device, wherein the transport lock assembly comprises a powerpack ( 30 ) having a locking member ( 50, 50′, 50 ″) configured to interact with a control member ( 60 ), which locking member ( 50, 50′, 50 ″) is movable, relative to the control member ( 60 ), from a first state in which the control member ( 60 ) is immobilized, to a second state in which the control member ( 60 ) is free to move; wherein the transport lock assembly further comprises a housing part ( 20 ) having a key member ( 22 ), such that assembly of the powerpack ( 30 ) with the housing part ( 20 ) causes the key member ( 22 ) to move the locking member ( 50, 50′, 50 ″) from the first state to the second state.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a U.S. National Phase Application pursuant to35 U.S.C. § 371of International Application No. PCT/EP2018/061880 filedMay 8, 2018, which claims priority to European Patent Application No.17170306.9 filed May 9, 2017. The entire disclosure contents of theseapplications are hereby incorporated by reference into the presentapplication.

TECHNICAL FIELD

The present disclosure relates to a transport lock assembly for amedicament delivery device. More in particular, it relates to transportlock of a powerpack of a medicament delivery device.

BACKGROUND

The disclosure relates to medicament delivery devices that are deliveredas sub-assemblies for final assembly into, for instance, auto-injectors.One of the sub-assemblies may be a powerpack, which may comprise apre-tensioned plunger rod, arranged with a control member that isconfigured to release the pre-tensioned plunger rod in the assembledmedicament delivery device. For this reason, the control member ismovable, so that another element, typically comprised in a differentsub-assembly, may interact with control member when the user of themedicament delivery device intends to administer a dose of medicament.During transport of the sub-assemblies, vibrations, movements andimpacts may lead to accidental release of the pre-tensioned plungerrods, causing the powerpacks in question to be wasted. It is thereforenecessary to ensure that the control members are held securely so thatthey do not accidentally activate the powerpacks. At the same time, thelocked powerpacks must not become difficult or complicated to unlockand/or to assemble due to these security measures.

Some attempts have been made to solve these problems. WO2014/154491discloses a transport lock mechanism for a powerpack where an actuatorsleeve is prevented from axial movement during transportation. Duringassembly, a key member, arranged on an inner surface of a housing,interacts with the lock mechanism to rotate the actuator sleeve into aposition in which it may move axially after assembly. In the presentdisclosure, the control member is rotationally locked. Therefore adifferent mechanism is needed.

WO2016/169748, on the other hand, relates to a transport lock where apowerpack comprises a rotatable coupling member which controls therelease of a biased plunger rod. During transportation, the couplingmember is prevented from rotation by radially flexible tabs, such thatwhen the power pack is assembled with a housing, the tabs are pushedradially inwards to free the coupling member for rotation in theassembled medicament delivery device. Due to tolerances, the unlockingof the coupling member during assembly is not always successful, whichmay leady to malfunctioning medicament delivery devices.

SUMMARY

In the present disclosure, when the term “distal” is used, this refersto the direction pointing away from the dose delivery site. When theterm “distal part/end” is used, this refers to the part/end of thedelivery device, or the parts/ends of the members thereof, which underuse of the medicament delivery device is/are located furthest away fromthe dose delivery site. Correspondingly, when the term “proximal” isused, this refers to the direction pointing to the dose delivery site.When the term “proximal part/end” is used, this refers to the part/endof the delivery device, or the parts/ends of the members thereof, whichunder use of the medicament delivery device is/are located closest tothe dose delivery site.

Further, the term “longitudinal”, with or without “axis”, refers to adirection or an axis through the device or components thereof in thedirection of the longest extension of the device or the component.

The term “lateral”, with or without “axis”, refers to a direction or anaxis through the device or components thereof in the direction of thebroadest extension of the device or the component. “Lateral” may alsorefer to a position to the side of a “longitudinally” elongated body.

In a similar manner, the terms “radial” or “transversal”, with orwithout “axis”, refers to a direction or an axis through the device orcomponents thereof in a direction generally perpendicular to thelongitudinal direction, e.g. “radially outward” would refer to adirection pointing away from the longitudinal axis.

Also, if nothing else is stated, in the following description whereinthe mechanical structure of the device and the mechanicalinterconnection of its components is described, the device is in aninitial non-activated or non-operated state.

In view of the foregoing, a general object of the present disclosure isto provide a transport lock assembly for a powerpack of a medicamentdelivery device.

According to a main aspect of the disclosure it is characterised by atransport lock assembly for a powerpack of a medicament delivery device,wherein the transport lock assembly comprises a powerpack having aspring-biased drive member, a body for holding the spring-biased drivemember in a pre-tensioned state, a control member for releasing thespring-biased drive member from the body, and a locking memberconfigured to interact with the control member, which locking member ismovable, relative to the control member, from a first state in which thecontrol member is immobilized, to a second state in which the controlmember is free to move, the transport lock assembly being furthercharacterised by a housing part having a key member, which housing partis configured to receive the powerpack, and wherein assembly of thepowerpack with the housing part causes the key member to move thelocking member from the first state to the second state relative to thecontrol member.

The locking member thus connects with the control member and preventsthe control member from rotating when the locking member is in the firststate. The locking member is further disconnected from the controlmember when the power pack is assembled with the housing part, such thatthe locking member is moved to the second state, wherein the controlmember is free to rotate.

The body comprises radially flexible arms. The arms connect with anengagement member of the spring-biased plunger rod. In an initial stateof the control member, the control member prevents the arms from flexingradially outwards, out of engagement with the engagement member of theplunger rod. In a released state of the control member, relative to thebody, recesses on an inside surface of the control member align with thearms of the body. The recesses of the control member allow the arms toflex radially outwards, under a bias of a drive member spring, releasingthe spring-biased drive member to expel a medicament of a container.

According to another aspect of the disclosure the control member isrotationally movable around a longitudinal axis, but axially fixed,relative to the body, and the locking member is axially movable relativeto the body and relative to the control member.

Since the control member is axially fixed, the locking member willdisengage from the control member upon axial movement from the firststate to the second state.

According to another aspect of the disclosure, assembly of the powerpackwith the housing part comprises an axial movement of the powerpackrelative to the housing part such that the key member axially moves thelocking member from the first state to the second state.

Thus, the key member may be a structural feature of the housing part,which structural feature interacts with a surface, directly connected tothe locking member, to axially move the locking member from the firststate to the second state. The key member may also a structural featureof component contained in the housing part on assembly of the powerpackwith the housing part.

According to another aspect of the disclosure, the locking member, inthe first state, mates with a mating member of the control member suchthat rotation of the control member relative to the body and relative tothe locking member is prevented. The locking member, in the secondstate, is axially separated from the mating member of the control membersuch that rotation of the control member relative to the body andrelative to the locking member is allowed.

The mating member of the control member and the locking member may beany kind of mutually engaging structures, such as protrusions, ratchets,ribs, recesses, teeth, slits, etc, which prevent relative rotationbetween the control member and the locking member in the first state,but which allow relative rotation between the control member and thelocking member in the second state, and which also allow axialseparation, or disengagement, of the mating member and the lockingmember.

According to another aspect of the disclosure the body is coaxiallyarranged with the control member and the spring-biased drive member.

The body may be a tubular sleeve, accommodating the spring-biased drivemember.

According to another aspect of the disclosure the body is locatedradially outside the spring-biased drive member and radially inside thecontrol member, and the locking member is located axially next to thecontrol member.

As such, the control member may be a tubular sleeve which isrotationally arranged radially outside the body. The locking member mayalso be tubular, or ring-shaped, and may be axially movable relative to,and next to, the control member.

According to another aspect of the disclosure the locking member isarranged on a support member which is rotationally fixed relative to thebody.

Since the locking member is arranged on the support member, which isrotationally fixed relative to the body, the control member is alsorotationally fixed relative to the body, when the locking member is inthe first state. In other words, the locking member prevents the controlmember from rotational movement when the locking member is in the firststate.

According to another aspect of the disclosure the support member isaxially movable relative to the body and relative to the control member.

The locking member is arranged on the support member. Therefore, thelocking member is movable from the first state to the second state asthe support member moves axially relative to the control member.

According to another aspect of the disclosure the support member isaxially flexible.

The support member may be an axially flexible member, wherein axialcompression or extension of the flexible support member causes thelocking member to move from the first state to the second state.

According to another aspect of the disclosure the support member is anaxially flexible sleeve coaxially arranged with the body.

The support member may be an axially flexible sleeve, or tubular member,wherein axial compression or extension of the flexible support membercauses the locking member to move from the first state to the secondstate.

According to another aspect of the disclosure the support member is anaxially flexible, integrated, unitary part of the body.

To reduce the number of molded components of the device, the supportmember and the locking member may be integral with the body.

A flexible and/or resilient support member be advantageous in that itprovides an inherent resilient force which may return the locking memberinto engagement with the mating member of the control member in case themembers have been accidentally disengaged during handling or transportof the powerpack.

According to another aspect of the disclosure, a medicament deliverydevice comprises a transport lock assembly according to any of theforegoing aspects of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a perspective view of a semi-assembled medicament delivery deviceaccording to the present disclosure

FIG. 2 a cross-sectional view of the semi-assembled medicament deliverydevice of FIG. 1

FIG. 3 a perspective view of a housing part and of a powerpack of thepresent disclosure

FIG. 4 an exploded view of the powerpack of FIG. 3

FIG. 5a-b cross-sectional views of an assembled medicament deliverydevice according to the present disclosure

FIG. 6a-b perspective views of a powerpack according to a furtherembodiment of the present disclosure

FIG. 7a-b perspective views of a powerpack according to anotherembodiment of the present disclosure

DETAILED DESCRIPTION

FIGS. 1 and 2 show a medicament delivery device 10 in a semi-assembledstate in which a front assembly 80 has been mounted in a proximal partof a housing part 20 and in which a powerpack 30 has been partlyinserted via a distal end of the housing part 20.

The front assembly 80 comprises a pre-filled medicament container,having a movable stopper sealing a distal end of the container. Acontainer holder may be provided to retain the medicament containerwithin the housing part 20. A proximal end of the container may comprisea fixedly attached medicament delivery member, such as an injectionneedle or a mouthpiece. The medicament delivery member may alternativelybe designed to be attached to the container, via the container holder ata later stage, before use of the medicament delivery device. In case themedicament delivery member is a fixedly attached injection needle, aneedle sheath is provided to protect the injection needle in a sterileenvironment until the medicament delivery device 10 is ready for use.

A spring-biased tubular medicament delivery member guard is movablyarranged at a proximal end of the housing part 10. The medicamentdelivery member guard serves to protect and conceal the medicamentdelivery member, and to activate the powerpack 30 of an assembledmedicament delivery device.

The proximal end of the housing part 20 may further be provided with aremovable cap (not shown). In case the container has a fixedly attachedinjection needle with a needle sheath, the cap may also be provided witha needle sheath remover (not shown), such that the needle sheath isremoved from the needle when the cap is removed from the proximal end ofthe housing part 20.

FIG. 3 shows a main aspect of the present disclosure, namely the housingpart 20 and the powerpack 30 in an unassembled state. The constituentmechanical parts of the medicament delivery device 10 are transportedand delivered as sub-assemblies to a site where final assembly iscarried out. Final assembly means the process of assembling thesub-assemblies together with the pre-filled medicament container.

As shown in FIG. 4, the powerpack 30 comprises a spring-biased drivemember 70 (spring shown in FIG. 2), e.g. a plunger rod, a body 40 forholding the spring-biased drive member 70 in a pre-tensioned state, amovable control member 60 for releasing the spring-biased drive member70, and a locking member 50, configured to interact with the controlmember, which locking member 50 is movable, relative to the controlmember 60, from a first state in which the control member 60 isimmobilized, to a second state in which the control member 60 is free tomove.

The spring-biased drive member 70, further comprises a spring 77 (FIG.2), which is pre-tensioned between a proximal inner surface 71 of thedrive member 70, and distal inner stop wall 41 of the body 40.

The body 40 may be generally tubular, and may comprise a radiallyflexible holding member 46, such as an arm having an inward protrusion,which engages a corresponding holding member 76, e.g. a recess, of thespring-biased drive member 70, in order to hold the spring-biased drivemember 70 in the pre-tensioned state. The drive member 70 is coaxialwith the body 40 and is located radially inside the body 40. The controlmember 60 may be tubular and is coaxial with the body 40, and is furtherlocated radially outside the body 40. An inner surface of the controlmember 60 abuts the holding member 46 such that it is prevented fromflexing radially outwards under the bias of the spring 77 when thecontrol member 60 is in an initial state.

If the control member 60 is moved to a released state, such as byinteraction with the medicament delivery member guard, or by accident,recesses on the inside surface of the control member 60 align with theholding member 46 such that the holding member 46 may flex radiallyoutwards into the recesses, due to the spring 77 forcing thespring-biased drive member forward. Thereby the holding member 46 isforced outwards out of the corresponding holding member 76. When theholding member 46 is disengaged from the corresponding holding member76, the spring-biased drive member 70 will move proximally. If themedicament delivery device is completely assembled, the spring-biaseddrive member 70 will abut the stopper of the medicament container, andwill consequently drive the stopper forward, proximally, and expel amedicament through the medicament delivery member.

If the control member 60 is somehow, e.g. by accident, moved to thereleased state before the medicament delivery device 10 is completelyassembled, the spring-biased drive member 70 will be catapulted out ofthe powerpack 30, which may be harmful to a person handling the device.In addition, the powerpack 30 will be wasted.

In order to mitigate the problem of accidental activation of thepowerpack 30, the control member 60 must be prevented from moving to thereleased state prematurely.

In the exemplified embodiment, a locking member 50 is provided toprevent the control member 60 from moving relative to the body 40. Morein particular, the control member 60 is rotationally movable around alongitudinal axis, and axially fixed, relative to the body 40, and thelocking member 50 is axially movable, and rotationally locked relativeto the body 40 and relative to the control member 60. However, thelocking member 50 is configured to interact with the control member 60,such that when the locking member 50 is in the first state, the controlmember 60 is immobilized by the locking member 50. When the lockingmember 50 is moved to the second state the control member 60 is releasedby the locking member 50.

The locking member 50 may move either by axial displacement, e.g. alongthe body 40, or by axial compression, such that at least a part of thelocking member is compressed, causing the locking member 50 to disengagefrom the control member 60. The locking member 50 may alternatively moveby a combination of displacement and compression. The locking member 50may be located axially next to the control member 60.

The locking member 50 may comprise support member 56, which may be anannular or tubular member arranged around the body 40. The lockingmember 50 may further comprise and a mating member 52, arranged on thesupport member 56. The mating member 52 may be configured as alongitudinally elongated protrusion, which in the first state mates witha corresponding mating member 62 of the control member 60, such as alongitudinally elongated recess of the control member 60, such thatrotation of the control member 60 relative to the body 40 and relativeto the locking member 50 is prevented. In the second state, the matingmember 52 of the locking member 50, is axially separated from thecorresponding mating member 62 of the control member 60 such thatrotation of the control member 60 relative to the body and relative tothe locking member is allowed.

As shown in FIG. 4, the locking member 50 may comprise a fixing element53 which may interact with a corresponding fixing element 43 of the body40 such that the locking member 50 is axially movable but rotationallyfixed relative to the body 40. The fixing element 53 may be an inwardlydirected protrusion such as a rib, and the corresponding fixing element43 may be a longitudinally directed depression such as a groove or aslot in a side wall of the body 40. As is common in the art, interactingprotrusions and depressions may be interchanged between the components,such that the protrusion is instead arranged on the body 40 and thedepression is arranged on an inner wall of the locking member 50.

As described above, the movement of the locking member 50 may be anaxial displacement in relation to the body 40 and to the control member60, or an axial compression of the locking member 50, or a combinationof compression and displacement. As such, the displacement is a movementof the support member 56 and the mating member 52 arranged thereon. Thecompression movement is an axial compression of the support member 56such that the mating member 52 arranged thereon is axially displaced inrelation to the body 40 and to the control member 60.

The housing part 20 is configured to receive the powerpack 30. Thehousing part 20 comprises a key member 22 configured to interact withthe locking member 50, such that on assembly of the housing part 20 withthe power pack 30, the key member 22 axially moves the locking member 50from the first state to the second state. Thereafter, the control member60 is free to move to release the spring-biased drive member 70 uponactivation of the medicament delivery device 10.

The key member 22 may be configured as a distally directed ledge 22,provided at a proximal end of a longitudinal guide 26. The mating member52 of the locking member 50 may be configured as a guide follower suchthat the mating member 52 slides along the guide 26 when inserting thepowerpack 30 in the housing part 20.

Alternatively, the key member 22 may be configured as a structuralfeature, e.g. a ledge, or a protrusion, of any of the componentscomprised in the front assembly 80 in the housing part 20.

In a first embodiment, shown in FIGS. 1-5 b, the support member 56 ofthe locking member 50 is configured as a generally rigid annular ortubular member, arranged around the body 40. A stop element 48, such asa bump or a slight protrusion, is provided on an outer surface of thebody 40. The stop element 48 abuts the locking member 50 in the firststate, such that a certain threshold force is required to move thelocking member 50 from the first state to the second state, in order toprevent unintentional movement of the locking member 50.

Upon insertion of the powerpack 30 in the housing part 20, the matingmember 52 of the locking member 50 slides along the guide 26 of thehousing part 20. At a certain pre-determined position, the mating member52 makes contact with the key member 22. On application of said certainthreshold force the powerpack 30 may be further inserted into thehousing part 20, causing the key member 22 to axially move the lockingmember 50 from the first state (FIGS. 2 and 3) to the second state(FIGS. 5a and 5b ), during which movement the locking member 50 ridesover the stop element 48.

The locking member 50 is thereby displaced axially away from the controlmember 60, such that the control member 60 is free to move.

Towards the end of the insertion, fastening elements 44 of the body 40engage with corresponding fastening elements 24 of the housing part 20,e.g. by snap-fit engagement, such that the body 40, and consequently thepowerpack 30, and the housing part 20 are locked to each other.

In a second embodiment, shown in FIGS. 6a and 6b , a support member 56′of the locking member 50′ is configured as an axially resilientlycompressible annular, tubular, or sleeve-like member, arranged aroundthe body 40. A distal end of the support member 56′ rests against ablocking member 47 such that the support member 56′ is prevented fromdistal displacement. A mating member 52′ of the compressible supportmember 56′ is engaged with the corresponding mating member 62 of thecontrol member 60 (FIG. 6a ). A certain threshold force is required tocompress the support member 56′ axially in order to disengage the matingmember 52′ from the corresponding mating member 62 (FIG. 6b ).

Upon insertion of the powerpack 30 in the housing part 20, the matingmember 52′ of the locking member 50′ slides along the guide 26 of thehousing part 20. At a certain pre-determined position, the mating member52′ makes contact with the key member 22. On application of said certainthreshold force the powerpack 30 may be further inserted into thehousing part 20, causing the key member 22 to axially move, e.g.compress, the locking member 50′ from the first state (FIG. 6a ) to thesecond state (FIG. 6b ), during which movement the mating member 52′ isdisengaged from the corresponding mating member 62.

The resilience of the support member 56′ constantly biases the matingmember 52′ into engagement with the corresponding mating member 62.Therefore, if the mating member 50′ should be accidentally moved, i.e.compressed, during handling or transport of the powerpack 30, such as byan impact, the mating member 52′ will instantly re-engage with thecorresponding mating member 62 due to the resilience of the supportmember 56′.

In a third embodiment, shown in FIGS. 7a and 7b , a support member 56″of the locking member 50″ is configured as an axially resilientlycompressible member which is an integrated unitary part of the body 40.A distal end of the support member 56″ is integrated with the body 40such that the support member 56″ is prevented from distal displacement.A mating member 52″ of the compressible support member 56″ is engagedwith the corresponding mating member 62 of the control member 60 (FIG.7a ). A certain threshold force is required to compress the supportmember 56″ axially in order to disengage the mating member 52″ from thecorresponding mating member 62 (FIG. 7b ).

Upon insertion of the powerpack 30 in the housing part 20, the matingmember 52″ of the locking member 50″ slides along the guide 26 of thehousing part 20. At a certain pre-determined position, the mating member52″ makes contact with the key member 22. On application of said certainthreshold force the powerpack 30 may be further inserted into thehousing part 20, causing the key member 22 to axially move, e.g.compress, the locking member 50″ from the first state (FIG. 7a ) to thesecond state (FIG. 7b ), during which movement the mating member 52″ isdisengaged from the corresponding mating member 62. The locking member50″ is thereby moved axially away from the control member 60, such thatthe control member 60 is free to move.

An integrated locking member 50″ means fewer components to assemble andreduces the tolerance chain, which leads to a more robust and reliabledevice.

Furthermore, as discussed above in conjunction with the secondembodiment, the resilience of the locking member 50″ will cause themating member 52″ to re-engage with the corresponding mating member 62if the locking member 50″ should be accidentally moved during handlingor transport of the powerpack 30.

The invention claimed is:
 1. A transport lock assembly for a medicamentdelivery device, wherein the transport lock assembly comprises: apowerpack comprising: a spring-biased drive member; a body for holdingthe spring-biased drive member in a pre-tensioned state; a movablecontrol member for releasing the spring-biased drive member; and alocking member located axially next to the control member and is movablerelative to the control member from a first state where the controlmember is immobilized to a second state where the control member is freeto move; and a housing part comprising a key member, where the housingpart is configured to receive the powerpack, wherein the body iscoaxially arranged with the control member and the spring-biased drivemember, wherein the body is located radially outside the spring-biaseddrive member and radially inside the control member, wherein assembly ofthe powerpack with the housing part causes the key member to move thelocking member from the first state to the second state.
 2. Thetransport lock assembly according to claim 1, wherein the control memberis rotationally movable around a longitudinal axis, but axially fixedrelative to the body, and wherein the locking member is axially movableand rotationally fixed relative to the body and relative to the controlmember.
 3. The transport lock assembly according to claim 2, wherein thelocking member comprises a support member which is rotationally fixedrelative to the body.
 4. The transport lock assembly according to claim3, wherein an axial movement of the locking member is an axialcompression of the locking member, or an axial displacement of thelocking member, or a combination of both.
 5. The transport lock assemblyaccording to claim 4, wherein the locking member is axially resilientlycompressible.
 6. The transport lock assembly according to claim 5,wherein the locking member is an axially resiliently compressible sleevecoaxially arranged with the body.
 7. The transport lock assemblyaccording to claim 3, wherein the locking member is an axiallyresiliently compressible, integrated, unitary part of the body.
 8. Thetransport lock assembly according to claim 1, wherein assembly of thepowerpack with the housing part comprises an axial movement of thepowerpack relative to the housing part such that the key member axiallymoves the locking member from the first state to the second state. 9.The transport lock assembly according to claim 8, wherein the lockingmember comprises a mating member, which in the first state mates with acorresponding mating member of the control member, such that rotation ofthe control member relative to the body and relative to the lockingmember of the locking member, is axially separated from thecorresponding mating member of the control member such that rotation ofthe control member relative to the body and relative to the lockingmember is allowed.
 10. A medicament delivery device comprising atransport lock assembly according to claim 1.